Which expression does not have a greatest common factor?

a 2 x 2 + 8 x + 4

b 3x^2-12
c 9x2-16

Write a polynomial function f of least degree that has rational coefficients, a leading coefficient of 1, and the given zeros. 3, 4+2i, 1+(sqrt)7 the answer is supposed to be: f(x)=x(^5)-13x(^4)+60x(^3)-82x(^2)-144x+360 what am i doing wrong?

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab

Ron has 8 caps and 4 of his caps are blue. thes rest of his cap are red. how many of ron's caps are red